I've never had to, nor have I seen anyone that has. Well, maybe if you're quadrupiling a quantity. (example, 2/3 cup of butter x4), but for most people, I haven't seen a need for it.
" ... multiply by the RECIPROCAL of the divisor.
multiply and divide fractions!-.-
When we simplify fractions.
No, you cannot use models to multiply fractions!!
You use fractions for LOTS of things in the real world like money, gambling, shopping, clothing, etc.
when simplifying fractions
in cookbooks and recipes
In calculating fractions.
You multiply the fractions
When you add or subtract fractions you cross multiply and when you multiply or divide fractions you across multiply.
Yes you do.
there are None!